If just removing the logic board, I don’t find it necessary to disconnect the top fan connector. It connects to the fan mounted on the logic board , so it doesn’t need to be disconnected when removing the logic board itself.
Because there’s a magnet in the latch button assembly, small bits of anything ferrous that fell apart inside the laptop have a tendency to get stuck in the mechanism. I thought I needed to replace a latch because it appeared was broken; instead, when I disassembled it, a couple of hunks of metal bits came out. Then, when reassembled, it worked perfectly!
I suspect you are meant to remove the two T8 Torx screws holding down the drive retaining bar on the other side of the hard drive. Once the bar is removed, the drive will pivot out without having to touch the screws on the battery housing wall side.
I don’t believe you need to deroute the speaker cable; just disconnect it from the logic board and leave it taped on where it is.